From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <gdb-prs-return-14518-listarch-gdb-prs=sources.redhat.com@sourceware.org>
Received: (qmail 30369 invoked by alias); 30 Oct 2013 19:07:39 -0000
Mailing-List: contact gdb-prs-help@sourceware.org; run by ezmlm
Precedence: bulk
List-Id: <gdb-prs.sourceware.org>
List-Subscribe: <mailto:gdb-prs-subscribe@sourceware.org>
List-Archive: <http://sourceware.org/ml/gdb-prs/>
List-Post: <mailto:gdb-prs@sourceware.org>
List-Help: <mailto:gdb-prs-help@sourceware.org>, <http://sourceware.org/lists.html#faqs>
Sender: gdb-prs-owner@sourceware.org
Received: (qmail 30335 invoked by uid 48); 30 Oct 2013 19:07:38 -0000
From: "macro@linux-mips.org" <sourceware-bugzilla@sourceware.org>
To: gdb-prs@sourceware.org
Subject: [Bug gdb/16101] New: gdb.base/dprintf.exp agent-printf failures with
 non-Z0-supporting gdbservers
Date: Wed, 30 Oct 2013 19:07:00 -0000
X-Bugzilla-Reason: CC
X-Bugzilla-Type: new
X-Bugzilla-Watch-Reason: None
X-Bugzilla-Product: gdb
X-Bugzilla-Component: gdb
X-Bugzilla-Version: HEAD
X-Bugzilla-Keywords: 
X-Bugzilla-Severity: normal
X-Bugzilla-Who: macro@linux-mips.org
X-Bugzilla-Status: NEW
X-Bugzilla-Priority: P2
X-Bugzilla-Assigned-To: unassigned at sourceware dot org
X-Bugzilla-Target-Milestone: ---
X-Bugzilla-Flags:
X-Bugzilla-Changed-Fields: bug_id short_desc product version bug_status
 bug_severity priority component assigned_to reporter cf_gcctarget
Message-ID: <bug-16101-4717@http.sourceware.org/bugzilla/>
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: 7bit
X-Bugzilla-URL: http://sourceware.org/bugzilla/
Auto-Submitted: auto-generated
MIME-Version: 1.0
X-SW-Source: 2013-q4/txt/msg00144.txt.bz2

http://sourceware.org/bugzilla/show_bug.cgi?id=16101

            Bug ID: 16101
           Summary: gdb.base/dprintf.exp agent-printf failures with
                    non-Z0-supporting gdbservers
           Product: gdb
           Version: HEAD
            Status: NEW
          Severity: normal
          Priority: P2
         Component: gdb
          Assignee: unassigned at sourceware dot org
          Reporter: macro@linux-mips.org
            Target: arm-linux-gnueabi, mips-linux-gnu, powerpc-linux-gnu

There is an issue with agent dprintf on targets where `gdbserver' does
not support the `Z0' packet.  There GDB inserts software breakpoints
itself, by poking at memory explicitly to modify the instruction stream.
This includes dprintf breakpoints.  Once such a breakpoint has hit
`gdbserver' reports the hit to GDB (without executing the dprintf
request).  GDB in turn sees `agent-printf' in the list of breakpoint
commands and complains:

May only run agent-printf on the target

This is observed in GDB testing:

FAIL: gdb.base/dprintf.exp: 1st dprintf, agent
FAIL: gdb.base/dprintf.exp: 2nd dprintf, agent

on at least the arm-linux-gnueabi, mips-linux-gnu and powerpc-linux-gnu
targets.

I think it would be consistent if agent dprintf was not allowed for GDB
breakpoints.  However disabling the breakpoint commands feature on such
targets altogether would regress hardware (`Z1') breakpoints where
supported, so it looks to me that agent dprintf should be a
per-breakpoint feature, resorting to one of the other styles (probably
gdb) for GDB breakpoints.

-- 
You are receiving this mail because:
You are on the CC list for the bug.